Searching date between two given Dates - sql-server

Question

I have two specific dates.
lets say from 2014-04-04 To 2015-10-04.
I have a plan that says classes of Blah course will be on mon, wed and Fri.
Now I want to get the dates of each mon, wed and Fri from 2014-04-04 to 2015-10-04.

Answer 1

With a calendar table it is simple:
SELECT t.*
FROM dbo.TableName t
INNER JOIN CalendarTable c
ON t.DateColumn = c.Date
WHERE c.Date between '2014-04-04' AND '2015-10-04'
AND DATEPART(dw, c.Date) IN (1,3,5)
How to generate a calendar table (look for "Calendar table").

Answer 2

The standard reply to this by any seasoned SQL Server veteran, would be to create a calendar table. But all too often this is scoffed. So here's a slow and out-of-the-box method:
DECLARE #startDate DATE = '2014-04-04', #endDate DATE = '2015-10-04';
WITH CTE(N) AS (SELECT 1 FROM (VALUES(1),(1),(1),(1),(1),(1),(1),(1),(1),(1))a(N)),
CTE2(N) AS (SELECT 1 FROM CTE x CROSS JOIN CTE y),
CTE3(N) AS (SELECT 1 FROM CTE2 x CROSS JOIN CTE2 y),
CTE4(N) AS (SELECT 1 FROM CTE3 x CROSS JOIN CTE3 y),
CTE5(N) AS (SELECT 1 FROM CTE4 x CROSS JOIN CTE4 y),
CTE6(N) AS (SELECT 0 UNION ALL
SELECT TOP (DATEDIFF(day,#startDate,#endDate))
ROW_NUMBER() OVER(ORDER BY (SELECT NULL))
FROM CTE5),
TALLY(N) AS (SELECT DATEADD(day, N, #startDate)
FROM CTE6
WHERE DATENAME(weekday,DATEADD(day, N, #startDate)) IN ('Monday','Tuesday','Wednesday'))
SELECT N
FROM TALLY
ORDER BY N;

Answer 3

You can use a Recursive CTE if you do not have numbers table. Something like this. Note that the DATEPART(weekday,Dates) IN(1,3,5) is based on your setting of SELECT ##DATEFIRST.
For example If ##DATEFIRST is 1 then use DATEPART(weekday,Dates) IN(1,3,5)
DECLARE #StartDate DATETIME
DECLARE #EndDate DATETIME
SET #StartDate = '2014-04-04'
SET #EndDate = '2015-10-04'
;WITH CTE AS
(
SELECT #StartDate Dates
UNION ALL SELECT DATEADD(d,1,Dates) FROM CTE WHERE DATEADD(d,1,Dates) <=#EndDate
)
SELECT Dates,DATENAME(weekday,Dates) FROM CTE
WHERE DATEPART(weekday,Dates) IN(1,3,5)
OPTION (MAXRECURSION 0);
GO

Answer 4

DECLARE #StartDate DATETIME
DECLARE #EndDate DATETIME
SET #StartDate = '2014-04-04'
SET #EndDate = '2015-10-04'
;WITH CTE AS
(
SELECT #StartDate Dates
UNION ALL SELECT DATEADD(d,1,Dates) FROM CTE WHERE DATEADD(d,1,Dates) <=#EndDate
)
SELECT Dates,DATENAME(weekday,Dates) FROM CTE
WHERE DATEPART(weekday,Dates) IN(1,3,5)
OPTION (MAXRECURSION 0);
GO
--- thanks to #ughai

Answer 5

I've comeup with another way to do this.
this query will not only Show the dates in between but also it will compare the dates u want to compare with.
Q.Dates Comparison
DECLARE #StartDate DATETIME
DECLARE #EndDate DATETIME
SET #StartDate = '2014-12-22'
SET #EndDate = '2015-02-13'
drop table #TabCourseDetailID
SELECT ROW_NUMBER() OVER(ORDER BY CourseDetailID asc) AS Row,
CourseDetailID
into #TabCourseDetailID
from coursedetail
where UnitType='T' and courseID =1
Declare #counter as int
Declare #CourseDetailID varchar(500)
set #counter = 0
Declare #TempTable Table (FirstValue datetime,LastValue int)
while #StartDate <= #EndDate
begin
If DATEPART(WeekDay,#StartDate) IN (2,4,6)
begin
Set #Counter = #counter+1
Select #CoursedetailId=CoursedetailId
from #TabCourseDetailID
where row=#counter
insert into #TempTable (FirstValue,LastValue)
values (#StartDate,#CoursedetailId)
end
set #StartDate =DATEADD(d,1,#StartDate)
end
select t.LastValue,
t.FirstValue,
bp.conductedDate
from batchprogress bp
Join #TempTable t on (t.LastValue=bp.CoursedetailID)
where CourseID =1 and batchID =5
order by t.lastvalue